Electronic Processes in Zinc Fluoride and in the Manganese-Activated Zinc Fluoride Phosphor

Publisher Website
Google Scholar
Abstract
Measurements have been made of the temperature‐dependence of electrical conductivity and thermal e.m.f. on ZnF2 and ZnF2:Mn, and of the Hall coefficient and rectifying power at 25°C on ZnF2. Both ZnF2 and ZnF2:Mn are N‐type impurity semiconductors. The presence of MnF2 in ZnF2 decreases the electronic conductivity by a factor of about 103, indicating a decrease in the concentration of electron donors by oxidation. A marked dependence of the temperature variation of conductivity on heat treatment has been observed. Contrary to the simple theory, the absolute values of the thermal e.m.f. increase with temperature. From the Hall coefficient and conductance at 25°C of heat‐treated ZnF2, a concentration of free electrons of 3×1016 cm−3 and a mean free path of 6.7×10−8 cm are deduced. ZnF2 rectifies in the expected direction.